Hi all! I'll be heading to Mexico over Christmas, for a three week visit. I'd like to take a few days to climb Citlaltepetl. I'm looking for input on various practicalities, and how I should schedule the climb, given my previous experience.

Previous high altitude experience:
My most recent and relevant experience was Kazbek in the Caucasus (5033 m / 16512 ft, http://www.summitpost.org/mount-kazbek/154019), which I climbed in 2015. I did this over four days:
Day 1: Hike to basecamp at 3600 meters (12 000 ft).
Day 2: Acclimatization, including quick hike up to 4000 meters and back.
Day 3: Summit day.
Day 4: Return to civilization.

I experienced no obvious symptoms of AMS, but the sense of physical exertion got very noticeable from apx. 4500 meters (14 700 ft). A week ahead of Kazbek, I hiked through the Svaneti mountains, where, at one point, I reached almost 3000 meters (10 000 ft), which I suppose might have had some effect on my acclimatization.

1. Climbing schedule: Given the above, could I reasonably hope to climb Citlaltepetl after spending a full day acclimatizing at the Refugio (or thereabouts)? In other words, arrive there at Day 1, spend Day 2 at the Refugio (perhaps including a day hike to a higher elevation), and then summit on Day 3? Not asking for a guarantee here, just an estimate of whether this is realistic. Otherwise, I can set aside more time.

2. Guide/outfitter: I'd like to have a guide, both for the mountain and sorting the practicalities. I've seen a few offerings online, such as Orizaba Mountain Guides, offering 4-5 day packages at around 5-600 USD per person, starting in Tlachichuca/San Miguel Zoapan. Is this what I'd have to pay no matter what? I ask because from my experiences elsewhere, quotes on English-language websites oriented towards international tourists have often been drastically higher than the prices you could get if you just book your hike there and then. Moreover, which outfitters are recommended? I've seen Orizaba Mountain Guides, Mexico Extreme and Servimont receive favorable mentions around these forums over the years. Are they still good? Understand, I'm willing to pay the cost of a good service, but I'd rather not needlessly pay double.

3. Finding climbing partners: I'd rather do this as part of a small group with a guide (or a larger group with several guides). How easy is it to find someone to climb with, and if so, where? Upon arriving Tlachichuca, or the Refugio, could I easily expect to find a group to join, or other singles to form a group with? Both for the social and economic aspect of it.

4. Gear: I have a pair of crampon-compatible La Sportiva Trango Guide Evo GTX boots. Is there any reason for me to buy and bring my own crampons/ice axe/harness from home, or will I get appropriate gear provided from whichever outfiter I do this with? Moreover, would I need to bring a sleeping bag from home for use at the Refugio? If possible I'd like to avoid lugging any extra volume and weight and around Mexico during the remaining two+ weeks of my trip there

5. Weather: What kind of wind/temperatures/weather should I be prepared for on the summit day (and night), in the first half of January?

1. Many people do it, but I would not if I were coming from sea level. 0 -> 5600 meters in 2.5 days is too fast for my taste. Unless I have spent some time in Mexico City or other high places before.
2. 500-600 USD is expensive for Mexico, but Christmas is high season. Our whole Malinche-Pico-Izta trip cost the two of us 550 USD total, airport to airport in 10 days, but we were pretty much autonomous. The Pico part (transport from Tlachichuca and 1 night and 2 meals in town) was 240 USD. Bus is cheap and simple in Mexico, so you can at least get to Tlachichuca or San Miguel by yourself to save some cash.
3. There will be a lot of people around, maybe even a full refuge (around 50 people?). Arranging to join a group from town should be easy. If you have some mountaineering experience, you should be able to find partners from town or refuge.
4. They will rent everything that you need. Whatever needs to be sharp may be dull, but it will be adequate. Also consider using luggage storage at bus stations in Mexico City or Puebla if you have your own gear.
5. Can't help you with that. We went there in June.
Don't hesitate if you have more questions.

You could certainly do it, but there is a very high chance you could get AMS and be pretty sick too unless you spend some time up high acclimating more than you mentioned above. Depending on other commitments you have during your visit I would suggest doing a lower climb (or two) first such as La Malinche, Nevado de Toluca or Iztaccihuatl. I soloed Izta + Orizaba several years ago, and a few years ago returned to guide friends up NdT, Izta + Orizaba. None of us had altitude problems, but we live a little above sea level in Denver. You will enjoy the climb more if you find a way to get another peak in. I actually enjoyed Izta much more than Orizaba.

Also, I would consider taking Diamox. Some suggest taking 600mg Ibuprofen prior to climbing, but that only prevents the headache which could mask the early symptoms of AMS which you need to recognize early to avoid getting really sick should you develop it.

I went in January and February which was nice both times I went there. It wasn't too cold, maybe a little below 0 C, but could be windy.

I believe you can rent crampons and maybe a bag with the outfitters you mentioned. Your best chance to climb with a group is likely by making arrangements prior to arriving in Tlachichuca.

Best wishes,

Woodie

Thank you both, to the point and very helpfull!

By the time I do Citlaltepetl, I'll have spent a week or more in Mexico, possibly in Mexico City. So, depending on how I schedule things, I could at least be acclimatized to that altitude (apx. 7500 feet) by that time.

I'm not in a great hurry, so using an extra day, for example to acclimatize at the Refugio or at some lower location, is no trouble. However, taking several additional days to do another significant peak beforehand may be stretching it. How much time would a combo with Malinche realistically take? Assuming I'd be doing it after 4-7 days spent in the Mexico City area.

Would it be fair to assume that if I go with a reputable outfitter, they'd watch over whatever stuff I leave behind at the Refugio on summit day etc.? I see reports about thefts there, and while I'll keep in mind nixoriugis' suggestion about using luggage storage at bus stations, there's still stuff I'd still like to bring along to the Refugio, but wouldn't want to drag along all the way to the top.

I think your chances are good if you are already acclimatized to Mexico City, but there is still risk. Malinche or Toluca are both one day affairs, but if you're not interested in them, I think that it would be better to spend that extra day on Pico de Orizaba since you would also be sleeping at high elevation and you would have time to scout the route.
I don't think the outfitters would have someone watch over your stuff, but I am pretty sure this service can be had for extra money. We had no problem leaving gear caches and high camps unattended, but only left food and basic stuff in the refuge. I personally treat any car-accessible place as vulnerable to theft, but people do leave sleeping gear there. Again, we were there in June, where we only met 3 parties in 4 days on the mountain.